Throttle valve arrangement for a combustion engine

ABSTRACT

In a combustion engine having a suction conduit, a throttle valve is placed into said suction conduit for controlling the gas and air mixture flow to the engine combustion spaces, a spring arrangement operatively coupled to the throttle valve and tending to return the throttle valve into an idle run position when an actuating force through the accelerator pedal is discontinued, the spring arrangement including a first spring and a second spring, the second spring being coupled to the throttle valve for rotating the throttle valve if the first spring is broken into a position of the throttle valve corresponding substantially to the idle position of the engine but in a direction of rotation opposite to the direction of rotation by the first spring, the first spring exerting a momentum on the throttle valve larger than the momentum exerted by the second spring resulting in a difference in momenta rotating the throttle valve into its idlerun position when the actuating force is discontinued.

United States Patent 1191 Hiesterm ann 1 Jan. 21, 1975 THROTTLE VALVE ARRANGEMENT FOR A COMBUSTION ENGINE [75] Inventor: Kurt Hiestermann,Tappenbeck,

Germany [22] Filed: Dec. 28, 1973 [21] Appl. No.: 429,134

[30] Foreign Application Priority Data Primary ExaminerCharles J. Myhre Assistant Examiner-Ira S. Lazarus Attorney, Agent, or FirmErnest F. Marmorek [57] ABSTRACT In a combustion engine having a suction conduit, :1 throttle valve is placed into said suction conduit for controlling the gas and air mixture flow to the engine combustion spaces, a spring arrangement operatively coupled to the throttle valve and tending to return the throttle valve into an idle run position when an actuating force through the accelerator pedal is discontinued, the spring arrangement including a first spring and a second spring, the second spring being coupled to the throttle valve for rotating the throttle valve if the first spring is broken into a position of the throttle valve corresponding substantially to the idle position of the engine but in a direction of rotation opposite to the direction of rotation by the first spring, the first spring exerting a momentum on the throttle valve larger than the momentum exerted by the second spring resulting in a difference in momenta rotating the throttle valve into its idle-run position when the actuating force is discontinued,

3 Claims, 2 Drawing Figures Patented Jan. 21, 1975 2 Sheets-Sheet 1 Fig.1

Patented Jan. 21, 1975 5 3,861,377

2 Sheets-Sheet 2 THROTTLE VALVE ARRANGEMENT FOR A COMBUSTION ENGINE FIELD OF THE INVENTION The present invention relates to a throttle or butterfly valve arrangement for a combustion engine having a throttle or butterfly valve in a suction conduit and which is associated with a spring means in such a manner that the spring attempts to retain the throttle or butterfly valve in a position corresponding to the idle run of the engine against an actuating force acting on the throttle. Such actuating force in a motor vehicle usually corresponds to the force applied onto the accelerator. Under the term suction conduit within the scope of the present invention one should understand also the carburetor in the event the combustion engine is provided with suchcarburetor.

BACKGROUND OF THE INVENTION In throttle or butterfly valve arrangement of the above described type there is the danger present that if the spring is broken then the throttle valve will not be moved back into the idle run position if the actuating force is not present. As a result the throttle valve will not follow the instructions coming from the driver of the vehicle and instead will cause a running of the engine at a very high number of revolutions which could lead to serious accidents.

United States safety standards require that at least two energy sources must be present which operate on the throttle valve such, that in the event one of the energy sources becomes inoperative the other will still be able to return the throttle valve to its idle run position. If in order to satisfy the above requirements, one would employ a pair of parallel lying spring means each of which is designed to contribute half of the momentum usually provided to return the throttle valve into its idle run position, then the pivoting of the butterfly or throttle valve into its idle run position in the event one of the springs is broken, would require a relatively long time, that is, would come about relatively slowly.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide an improved resetting spring arrangement for the throttle or butterfly valve of a combustion engine which reliably returns the throttle valve into a position corresponding to the idle run position of the combustion engine when the actuating force acting on the throttle valve is discontinued.

Accordingly, the present invention provides that in a throttle or butterfly valve arrangement in a combustion engine a second spring is associated with the throttle valve in such a manner that in the event that the first spring is broken then the second spring will pivot the throttle valve in the opposite direction than the pivoting effect of the first spring was and it will put the throttle valve into approximately its idle run position which is defined by the abutting position of the butterfly valve, and that the momentum exerted by the first spring onto the throttle valve is so much larger than the momentum exerted onto the butterfly valve by the second spring, that the difference between the momenta exerted by the two spring means when the actuating force acting on the throttle valve is discontinued will be able to pivot the throttle valve into a position corresponding to the idle position of the engine.

According to the present invention it is assured that the measures of the two spring means is such that under conventional operating conditions, that is. without a break in any one of the spring means, the two spring means will exert onto the throttle valve such a momentum which substantially corresponds to the momentum produced by the other spring and the actuating force acting on the throttle valve, that is the force on the accelerator pedal, must be increased in order to return the throttle valve into an open position. Ifnow the actuating force is discontinued then the first spring means will return the throttle valve quicker to the position corresponding to the idle run position than it would be done by the second spring. In the event the first spring becomes broken, the second spring provides for a desired reduction of the number of revolutions of the engine by that it will return the throttle valve into a rest position corresponding approximately to the idle run position of the engine. Inasmuch as under normal conditions the valve arrangement is effected only by the difference of the momenta of the two springs, the second spring means can be constructed strong enough that it will be able to pivot the throttle valve into the rest position with sufficient speed.

According to the present invention the actuating force is transmitted to the throttle valve by means of a drag lever which is coupled to the throttle valve or to a pivot axle thereof in such a manner that it will not prevent a pivoting movement of the throttle valve into its rest or abutting position in the event the first spring is broken. Consequently such pivoting of the throttle valve will come about independently from any setting of the accelerator pedal.

Inasmuch as here a pivoting movement must take place into a position which is shifted by about with respect to the idle-run position and the second spring must be effective accordingly over a large angular region, it is preferred according to the present invention to construct the second spring as an operating lever spring coupled to one of the pivot axles of the throttle valve.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will become more readily apparent from the following description of preferred embodiments thereof shown, by way of example, in the accompanying drawings in which:

Both figures are schematic illustrations of spring arrangements associated with a throttle or butterfly valve of a combustion engine according to the present invention.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT It is noted that the present invention is applicable to combustion engines, a carburetor is used or not and whether a single suction conduit it present or several of them are operable. With reference to the both figures it is noted that in the suction conduit 1 of the combustion engine a throttle or butterfly valve 2 is mounted in a conventional manner, therefore, details of the mounting are not illustrated. The solid line illustration of the butterfly valve 2 shows it in its idle run position, that is, in a position which corresponds to the idle run of the engine. The throttle valve 2 is actuated by a force which is schematically illustrated by the arrow 7 and which is acting through an operating drag lever 8 and pivots the throttle valve 2 about a pivot axle 3. As can be seen in the FIG. 1 a first spring and a second spring 6 are also acting through a lever arm 4 onto the throttle valve 2 by being coupled to its pivot axle 3. In FIG. 2, the second spring is constructed as an operating lever spring 9 set onto the pivoting axle 3. One leg 11 of the operating lever spring is fastened to the suction conduit 1, its other leg 12 to the axle 3 extending into a recess therein. The second spring will produce a smaller momentum than the first spring 5 onto the throttle valve 2. The difference of the momenta exerted by the two springs 5 and 6 or 9 respectively is large enough that in the event that the actuating force 7 will be discontinued acting on the drag lever 8 and, consequently onto the throttle valve 2, it will be able by the effect of the first spring 5 to return the throttle 2 into the idle run position and retain same therein, that is, if the actuating force 7 suddenly becomes discontinued, then it will be able to return the throttle valve 2 into its idle run position within a certain predetermined time.

Such time requirement is also met and retained even if there is a break in the second spring 6 or 9. In such case the gas control of the combustion engine will require a larger actuating force 7.

In the event that there is a break in the first spring 5, then the second spring 6 or 9 respectively becomes free and will pivot, in FIG. 1 through the drag lever 8, the valve 2 into a rest position indicated by 2' which corresponds at least to the idle run position of the engine.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

Having thus described the invention, what I claim as new and desire to be secured by Letters Patent, is as follows:

1. In a combustion engine having a suction conduit, a throttle valve placed into said suction conduit for controlling the gas and air mixture flow to the engine combustion spaces, a spring arrangement operatively coupled to said throttle valve and tending to return said throttle valve into an idle run position when an actuating force through the accelerator pedal is discontinued, said spring arrangement comprising a first spring means and a second spring means, said second spring means being coupled to said throttle valve means for rotating said throttle valve means when said first spring means is broken into a position of said throttle valve means corresponding substantially to the idle position of the engine but in a direction of rotation opposite to the direction of rotation by said first spring means, said first spring means exerting a momentum on said throttle valve larger than the momentum exerted by said second spring means resulting in a difference in momenta rotating the throttle valve into its idle-run position when said actuating force is discontinued.

2. The combination as claimed in claim 1, wherein means are provided for coupling said actuating force to said throttle valve, said means comprising a drag lever means.

3. The combination as claimed in claim 1, wherein said second spring means comprises an operating lever spring set onto the pivot axle of said throttle valve and directly operating on said pivot axle. 

1. In a combustion engine having a suction conduit, a throttle valve placed into said suction conduit for controlling the gas and air mixture flow to the engine combustion spaces, a spring arrangement operatively coupled to said throttle valve and tending to return said throttle valve into an idle run position when an actuating force through the accelerator pedal is discontinued, said spring arrangement comprising a first spring means and a second spring means, said second spring means being coupled to said throttle valve means for rotating said throttle valve means when said first spring means is broken into a position of said throttle valve means corresponding substantially to the idle position of the engine but in a direction of rotation opposite to the direction of rotation by said first spring means, said first spring means exerting a momentum on said throttle valve larger than the momentum exerted by said second spring means resulting in a difference in momenta rotating the throttle valve into its idle-run position when said actuating force is discontinued.
 2. The combination as claimed in claim 1, wherein means are provided for coupling said actuating force to said throttle valve, said means comprising a drag lever means.
 3. The combination as claimed in claim 1, wherein said second spring means comprises an operating lever spring set onto the pivot axle of said throttle valve and directly operating on said pivot axle. 